The topic of hyper-extension of the back during kettlebell training comes up frequently, especially with beginners.
It’s completely understandable.
Let’s clear something up right away, first of all, back hyper-extensions when done right—and they’re done everyday on the GHD—are incredible good for you. Like with any exercise, it’s not something you do day one, you have to work on strength and flexibility first.
Now the other news, what you see in kettlebell sport or kettlebell training, is not back (thoracic spine) hyper-extension, it’s hip extension with a crunch (or thoracic flexion if you want to get technical).
At 45 seconds in you can you see hip extension and thoracic flexion.
What is hip (hyper-)extension?
Hip flexion is where you pull the top of the pelvis down towards the ground, extension is the opposite. Hip hyperextension is not something everyone can do right away, you need flexibility at the front, something you’ll need to work on over a period of time.
Hip hyperextension, i.e. in a neutral position you’d be in extension, and going further back, i.e. pulling the pelvis further back, is called hip hyper-extension (hyper is going past). But most people associate an injury with the word hyper-extension, and its definition is:
Hyper-extension is an excessive joint movement in which the angle formed by the bones of a particular joint is opened, or straightened, beyond its normal, healthy, range of motion.
You create hip extension by squeezing the gluteals and letting the top of the femur come slightly forward, i.e. normally positioned above the ankles, now coming forward towards the toes. This action tilts the pelvis backward. On top of the pelvis is the spine, this follows along naturally—looking like back hyper-extension—if you keep it positioned neutrally.
The second step is to crunch, bring the shoulders and head forward, this is done via thoracic flexion, the same action you make when performing crunches on the ground.
No, one does not need to wear a belt, it’s the same as for deadlifting, it’s mostly used to create more tension, firmness in the lower abdomen, around the lumbar area (intra-abdominal pressure). It’s not to protect against what most people think is a bad position for the back. Back hyper-extension rather than hip extension would actually be a bad posture to use for training with heavyweights (unless doing Jefferson curls with the right weight).
A belt should be used as an aid, not in conjunction with weak core muscles. A lifter should always start without a belt, as technique and weight progress, the use of a belt can be introduced in training.
A belt is great for spinal integrity when dealing with previous injuries.
Together with the above info and our free racking PDF, you should be able to safely achieve a good rack soon.